Friday, 27th February 2009
How FriendFeed uses MySQL to store schema-less data. The pain of altering/ adding indexes to tables with 250 million rows was killing their ability to try out new features, so they’ve moved to storing pickled Python objects and manually creating the indexes they need as denormalised two column tables. These can be created and dropped much more easily, and are continually populated by an off-line index building process.
Magic properties make Firefox synchronously load the Java plugin. Even defining a function called sun() (or several other symbols) will trigger the Java VM to be loaded, dramatically hurting the performance of your page.
jQuery Sparklines. Delightful Sparklines implementation, using canvas or VML in IE. A neat nod towards unobtrusiveness as well: you can specify your data as comma separated values inside a span, then use a single jQuery method call to convert the span in to a sparkline image.